Intervertebral disc treatment devices and methods

ABSTRACT

Intervertebral disc treatment devices and methods are provided. An intervertebral disc treatment device includes a fibrous body sized for introduction into a disc cavity of a damaged disc wherein the body incorporates an effective amount of a tissue growth factor. Intervertebral disc treatment apparatuses are also described that include such a disc treatment device in combination with a delivery apparatus for retaining and selectively releasing the device into the disc cavity. Methods for treatment include providing a disc treatment device as described above and inserting the device into an opening in an annulus fibrous and into the disc cavity. The methods further include stimulating tissue growth within the disc cavity of the intervertebral disc.

BACKGROUND OF THE INVENTION

[0001] The present invention relates generally to devices and methodsfor restoring function to the spine. Specifically, the invention relatesto devices and methods for treating a damaged intervertebral disc whileretaining the annulus fibrosis of the disc and, advantageously,stimulating tissue formation to restore function to the original discstructure.

[0002] Back pain affects millions of people and is a common cause ofdisability for the middle-aged working population. A frequent cause ofback pain is rupture or degeneration of intervertebral discs.Intervertebral discs, located between the endplates of adjacentvertebrae, stabilize the spine, distribute forces between vertebrae, andcushion vertebral bodies. An intervertebral disc includes the annulusfibrosus, a structure that surrounds and confines an inner component,the nucleus pulposus. The annulus fibrosis is composed of a ring ofcollagen fibers and fibrocartilage embedded in a generally amorphousbase substance. The nucleus pulposus is comprised of a mucoid materialcontaining mainly glycoproteins and some collagen. In a healthy,undamaged spine, the annulus fibrosus prevents the nucleus pulposus fromprotruding outside the disc space and also resists torsional and bendingforces applied to the disc.

[0003] Intervertebral discs may be displaced or damaged due to diseaseor aging. Disruption of the annulus fibrosus can allow the nucleuspulposus to protrude into the vertebral canal or intervertebral foramen,a condition known as a herniated or slipped disc. A rupture in theannulus fibrosis can allow the escape of nucleus pulposus components.The extruded nucleus pulposus may press on a spinal nerve, which mayresult in nerve damage, pain, numbness, muscle weakness and paralysis.Furthermore, as a disc dehydrates and hardens due to age or disease, thedisc space height will be reduced, leading to instability of the spine,decreased mobility and pain. Moreover, excessive movement of the spinalsegments caused by the disc space height reduction could weaken theannulus fibrosus and, in certain cases, tear it.

[0004] Common methods of providing relief for damaged intervertebraldiscs include surgical removal of all or a portion of the intervertebraldisc, followed by fusion of the adjacent vertebrae. Although fusion caneliminate the above symptoms, the restricted motion of the fused segmentincreases the range of motion required of the adjoining intervertebraldiscs and could enhance their degeneration.

[0005] Attempts at overcoming the problems with fusion include replacingthe entire intervertebral disc with a mechanical, articulatingintervertebral disc spacer. Many of these devices utilize multicomponentpolymeric and metallic materials in an attempt to simulate the normal,healthy intervertebral disc motion. Such materials may disintegrate inthe body and break down under repeated stressing over prolonged periods.Other attempts at overcoming the problems with replacing the entireintervertebral disc have included replacing the nucleus pulposus withelastomeric materials such as hydrogels.

SUMMARY OF THE INVENTION

[0006] The present invention relates to methods and devices forrepairing an intervertebral disc which include promoting synthesis oftissue components, such as nucleus pulposus and/or annulus fibrosuscomponents, of the disc. In one aspect, the present invention provides adevice which can be used to promote the synthesis of disc components invivo to treat intervertebral discs. In particular, provided is a devicefor treating an intervertebral disc of a vertebrate while retaining anintact annulus fibrosis, the device including a compressible fibrousbody configurable to a compressed state for passage through an openingin the annulus fibrosis and into a disc cavity defined by the annulusfibrosis. The body is also configurable to an expanded state to residewithin the disc cavity and have a dimension greater than the opening soas to resist expulsion from the opening. The body incorporates aneffective amount of an active agent, such as a tissue growth factor, orcells (e.g. stem, nucleus pulposus, annulus fibrosis, or fibroblastcells), such cells optionally genetically modified to express effectiveamounts of a tissue growth factor, to stimulate tissue growth in thedisc structure.

[0007] Another aspect of the invention provides an intervertebral disctreatment device including a fibrous body sized for passage through anopening in the annulus fibrosis and into a disc cavity defined by theannulus fibrosis. The body is formed of fibers having coated thereon asolid carrier matrix incorporating a substance for promoting tissuegrowth.

[0008] In the above-discussed aspects of the invention, the body of thedevice may be partially or completely bioresorbable. In addition, thebody may be sized and configured to provide temporary or permanentprosthetic function, by being dimensioned to participate in thedistribution of compressive loads between adjacent vertebral bodies. Forexample, the body may be adapted to physically maintain a space in thedisc as new tissue is generated, and provide a substrate for tissueingrowth which locks the implant in place and reinforces regeneratedtissues to help maintain disc space height. In another inventive aspect,the body may be non-prosthetic, while delivering a substance forpromoting tissue growth in the disc structure. In such non-prostheticapplications, the device can be dimensioned, or can be formed of amaterial having compressive properties, such that it does notparticipate in the distribution of loads between the adjacent vertebralbodies. Nonetheless, such a non-prosthetic body may deliver the tissuegrowth substance so as to enhance the function or integrity of the discstructure.

[0009] Another feature of the invention provides an intervertebral discrepair apparatus that has a disc treatment device as described above incombination with a delivery apparatus. The delivery apparatus is adaptedto retain and selectively release the treatment device into the disccavity, and may for example include a member having a proximal end, adistal end and a lumen extending longitudinally therethrough. The discrepair device is disposed within the lumen of the apparatus. Thedelivery apparatus is adapted to translate the disc repair devicedistally through the lumen, through an opening in the annulus fibrosis,and into the disc cavity.

[0010] Yet other features of the invention include methods for treatingan intervertebral disc, which involve introducing a disc treatmentdevice as described above into the disc cavity of a damaged disc.

[0011] In additional embodiments of the invention, methods for treatinga disc having an annulus fibrosis having an opening therein, whichmethods include providing a body configured for passage through theopening and for blocking effluence from the opening once positionedwithin the disc cavity. The body is passed through the opening and intothe disc cavity, so as to block effluence from the opening. A tissuegrowth composition is also provided within the disc cavity, either as acomponent of the body or separately.

[0012] It is an object of the invention to provide devices and methodsthat may be used to provide therapy to a damaged disc by promoting invivo synthesis of components within the disc structure.

[0013] It is a further object of the invention to provide methods anddevices for preventing effluence from a damaged intervertebral disc.

[0014] These and other objects and advantages of the present inventionwill be apparent from the descriptions herein.

BRIEF DESCRIPTION OF THE FIGURES

[0015]FIG. 1 is a perspective view of a disc treatment device of thepresent invention.

[0016]FIG. 2 is an enlarged, cross-sectional view of the device of FIG.1 taken along a vertical plane through line 2-2 and viewed in thedirection of the arrows.

[0017]FIG. 3 is a perspective view of a further disc treatment device ofthe present invention having an annular ring shape.

[0018]FIG. 4 is a perspective view of a further disc treatment device ofthe present invention.

[0019]FIG. 5 is a side cross-sectional view illustrating the disc repairdevice shown in FIG. 1 positioned within an intervertebral disc.

[0020]FIG. 6 is a superior view of the disc treatment device of FIG. 1positioned in the disc cavity of an intervertebral disc.

[0021]FIG. 7 is a superior view of the disc treatment device of FIG. 3positioned in the disc cavity of an intervertebral disc.

[0022]FIG. 8 is a superior view of the disc treatment device of FIG. 4positioned in the disc cavity of an intervertebral disc.

[0023]FIG. 9 is a superior view illustrating two disc treatment devicespositioned in the disc cavity of an intervertebral disc, and wherein anopening in the annulus fibrosis is sealed with a sealant composition.

[0024]FIG. 10 is a superior view illustrating first and second disctreatment devices positioned within the disc cavity of an intervertebraldisc, wherein one functions to seal a rupture in the annulus fibrosis.

[0025]FIG. 11 is a side cross-sectional view of a disc treatmentapparatus, showing the disc treatment device of FIG. 3 in a compressedconformation in the lumen of a delivery apparatus.

[0026]FIG. 12 is a side cross-sectional view of a disc treatmentapparatus, showing the disc treatment device of FIG. 4 in a compressedconformation in the lumen of a delivery apparatus.

[0027]FIGS. 13 and 14 are superior views illustrating the use of thedisc treatment apparatus of FIG. 11 to release the disc treatment deviceof FIG. 3 into a disc cavity.

[0028]FIG. 15 is a perspective view of another disc treatment device ofthe invention.

[0029] FIGS. 16-18 illustrate elongate implants of the invention andapparatuses and methods for their introduction into the disc cavity.

[0030] FIGS. 19-21 illustrate elongate implants of the invention andadditional apparatuses and methods for their introduction into the disccavity.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0031] For the purposes of promoting an understanding of the principlesof the invention, reference will now be made to preferred embodimentsthereof and specific language will be used to describe the same. It willnevertheless be understood that no limitation of the scope of theinvention is thereby intended, such alterations and furthermodifications of the invention, and such further applications of theprinciples of the invention as illustrated herein, being contemplated aswould normally occur to one skilled in the art to which the inventionrelates.

[0032] The present invention provides intervertebral disc treatmentdevices, apparatuses and methods. Preferred devices include a fibrousbody configurable to smaller (compressed) and larger (relaxed)dimensional states. In the small configuration the body is adapted forpassage through an opening in the annulus fibrosis and into a disccavity defined by the annulus fibrosis. In the larger configuration thebody is dimensioned sufficiently to resist expulsion from the annulusopening when positioned within the disc cavity. The body incorporates aneffective amount of a substance which promotes tissue formation in thedisc structure. Inventive apparatuses are provided which include suchfibrous bodies in combination with a delivery apparatus adapted toretain and selectively release the bodies into the disc cavities, andinventive methods are also provided can be performed using the devicesand apparatuses of the invention.

[0033] Referring now to FIG. 1, a preferred intervertebral disctreatment device 11 is illustrated that includes an outer surface 12,and opposing ends 13. Device 11 is elongate in shape, having a generallycylindrical configuration with a circular cross-section. Device 11 has alength L and a cross-sectional dimension adapted for insertion into thedisc cavity of a damaged disk. In preferred devices, length L, will beabout equal to or less than a horizontal cross-sectional dimension ofthe disc cavity of a human disc (e.g. the anterior-posterior widthand/or the lateral width of the disc cavity), typically in the range ofabout 1.5 cm to about 3.5 cm. Preferably also, device 11 will be of asize and composition so as to avoid the exertion of substantial lateralpressure upon the annulus fibrosis by the device, which may cause orfacilitate the development of a rupture in the annulus fibrosis. Device11 will have or be compressible radially to have a greatestcross-sectional dimension which renders device 11 suited for insertioninto an opening in a disc annulus, such greatest cross-sectionaldimension typically being in the range of about 0.3 cm to about 2.0 cm.Device 11 may, for instance, have a body comprised of a woven ornonwoven fibrous material, including but not limited to a fibrous mesh.The body of device 11 is also preferably swellable in the presence ofaqueous fluids, for example swelling upon absorbing aqueous fluids intopores created between fibers in a fibrous body, and/or upon hydration ofthe fibers themselves.

[0034] Referring now to FIG. 2, shown is an enlarged, cross-sectionalview taken in a vertical plane along line 2-2 of FIG. 1 and viewed inthe direction of the arrows. As illustrated, device 11 may be formed asa roll of a sheet material, for instance a fibrous mesh, to provide amulti-layered device. Using such a multi-layered configuration, thedevice may be constructed to prevent, or alternatively to allow, forunrolling or unfolding of the layers after insertion into the disccavity. For instance, layers may be permanently affixed to one anothersuch as by bonding, crosslinking or stitching, to prevent unfolding. Onthe other hand, layers may be free of permanent affixation to oneanother (e.g. non-affixed or only temporarily affixed), to allow thelayers to unfold within the disc cavity. Such unfolding may, forexample, participate in configuring the device to resist expulsion froman annulus fibrosis opening, and/or to occupy a modified volume withinthe disc cavity for supporting tissue ingrowth.

[0035] Although a generally cylindrical disc repair device is shown inFIGS. 1 and 2, the device may assume a variety of other configurationsincluding spherical, rectangular, conical, ring, and other shapes. It ispreferred that the device be shaped so that it can facilitate blockingan opening in the annulus fibrosus of a damaged intervertebral disc whenpositioned in the disc cavity. For example, the device may have a firstend having a cross-sectional dimension smaller than anothercross-sectional dimension along the device, for example having anincreasing cross-sectional dimension along the device length such asoccurs in a generally conical device. Referring now to FIG. 3, such adisc repair device 21 is shown, having a generally conical shape with alarger end 22 and an outer surface 23 that tapers towards a smalleropposing end 24. As another example, the device may be collapsible inupon itself to have a smaller overall cross-sectional dimension in adirection in which it is to be inserted, for example in the case of anannular ring. Shown in FIG. 4 is such a disc treatment device 31, havingthe shape of an annular ring. Device 31 preferably has an outerdiameter, when expanded, approximating the horizontal width of the disccavity, and can be collapsed upon itself to adopt a smaller overallcross-sectional dimension for insertion through an opening in theannulus fibrosis.

[0036] With reference now to FIG. 5, shown is a side cross-sectionalview of a intervertebral disc having positioned therein disc treatmentdevice 11 of FIG. 1. As illustrated, an intervertebral disc 41 includesthe annulus fibrosus 42 formed from multiple layers of type IIcollagenous tissue, bounding an internal disc cavity 43. Disc treatmentdevice 11 is sized and configured to be contained within the disc cavityand in the illustrated embodiment has a vertical dimension to contactthe upper and lower surfaces of the disc cavity formed by end plates ofadjacent vertebrae. In addition, device 11 has a horizontal dimensionsubstantially spanning the horizontal width of the disc cavity 43.Device 11 also abuts the inner surface of the annulus fibrosus 42 so asto facilitate blockage of effluence from disc cavity 43 via opening 44in annulus fibrosus 42. Opening 44 in annulus fibrosis 42 often occursposterolaterally, where the annulus fibrosis is no longer supported bythe posterior longitudinal ligament. Thus, in most cases, device 11 orother disc treatment devices of the invention can be inserted via aposterolateral approach, although other approaches may be used whichcorrespond to the location of the rupture in the disc to be treated, orwhich involve insertion of the device through a conservative, alternateopening created in a spaced location from the rupture.

[0037] With reference now to FIGS. 6, 7, and 8, shown are superior viewsof disc treatment devices 11, 21, and 31, respectively, positionedwithin the disc cavity of a ruptured disc.

[0038] The disc treatment devices of the invention may be formed from awide variety of natural and/or synthetic materials, preferably naturaland/or synthetic polymers. Natural polymers include, for example,collagen, elastin, and cellulose and may be obtained from naturalsources by methods known to the skilled artisan, synthesized by methodsknown to those skilled in the art, or may be obtained commercially.Synthetic polymers which may be used in the present invention include,for example, polyamides, polyesters (e.g., Dacron), polyethylene,polyacrylonitrile, polyurethanes, polypropylenes or mixtures thereof.Combinations of natural and synthetic materials may also form anappropriate fibrous body for use in the present invention.

[0039] The preferred devices of the invention advantageously incorporatea tissue growth factor. In one embodiment, the device includes a liquidor solid carrier containing the tissue growth factor. For example, asolid or liquid carrier containing the growth factor may be used to coatthe exterior of the device, and/or may be incorporated withininterstitial spaces (e.g. pores) occurring internally of the device. Inaddition, or alternatively, a solid carrier matrix containing the growthfactor may be used to coat individual fibers from which the body of thedisc treatment device is formed. The growth factor is generally suitedto promote the formation of tissues, especially of the type(s) naturallyoccurring as internal or external components of the disc. For instance,the growth factor may promote the growth or viability of tissue or celltypes occurring in the nucleus pulposus such as nucleus pulposus cellsand chondrocytes, as well as space filling cells such as fibroblasts andconnective tissue cells such as ligament and tendon cells. Alternativelyor in addition, the growth factor may promote the growth or viability oftissue types occurring in the annulus fibrosus, as well as space fillingcells such as fibroblasts and connective tissue cells such as ligamentand tendon cells. Such growth factors include Transforming GrowthFactor-beta (TGF-B) and members of the TGF-B superfamily, FibroblastGrowth Factor (FGF) and members of the FGF family, Platelet DerivedGrowth Factor (PDGF) and members of the PDGF family, members of thehedgehog family of proteins, interleukins, Insulin-like Growth Factor(IGF) and members of the IGF family, colony-stimulating factor (CSF) andmembers of the CSF family, Growth Differentiation Factors (GDFs),Cartilage Derived Growth Factors (CDGFs), Cartilage Derived MorphogenicProteins (CDMPs), Bone Morphogenetic Proteins (BMPs), and mixturesthereof. BMPs are preferred.

[0040] A wide variety of BMPs have been identified and may be used inthe present invention. Human BMPs, especially recombinant human BMPs,are preferred, including for instance BMPs 1, 2, 3, 4, 5, 6, 7, 8, 9,10, 11, 12, 13, 14, 15, 16, 17 and 18. A variety of such BMPs haveproven effective for forming soft connective tissues such as cartilage(e.g. BMP-2 and BMP-4) or ligament and tendon (e.g. BMP-12 and BMP-13),and these and other similarly functional proteins are used withpreference in the instant invention. BMPs are available from GeneticsInstitute, Inc., Cambridge, Mass. and may also be prepared by oneskilled in the art as described in U.S. Pat. No. 5,187,076 to Wozney etal.; U.S. Pat. No. 5,366,875 to Wozney et al.; U.S. Pat. No. 4,877,864to Wang et al.; U.S. Pat. No. 5,108,932 to Wang et al.; U.S. Pat. No.5,116,738 to Wang et al.; U.S. Pat. No. 5,013,649 to Wang et al.; U.S.Pat. No. 5,106,748 to Wozney et al; and PCT Patent Nos. WO93/00432 toWozney et al.; WO94/2693 to Celeste et al.; and WO94/26892 to Celeste etal. All BMPs are contemplated whether obtained as above or isolated frombone. Methods for isolating BMP from bone are described in U.S. Pat. No.4,294,753 to Urist and in Urist et al., PNAS 371, 1984. Most preferably,the BMP or other growth factor will be non-osteoinductive or at theleast insufficiently osteoinductive to cause a bony fusion of thevertebrae above and below the disc under treatment.

[0041] In one aspect of the invention, BMP-12 and/or BMP-13 will beemployed in an effective amount to stimulate growth of ligament and/ortendon connective tissue within the disc cavity, for instance as may beevidenced by increased synthesis of proteoglycans and collagens.Recombinant human BMP-13 is most preferred in this regard.

[0042] A wide variety of materials may be utilized as solid carriers.Examples include natural polymers such as collagen, gelatin, elastin,cellulose, and the like.

[0043] In one preferred embodiment, the carrier is collagen. A widevariety of types of collagen may be used, including type I (foundprimarily in skin, tendon and bone), type II (found in cartilage), typeIII (found primarily in skin), fibrillar and non-fibrillar collagen. Thecollagen may be isolated from skin, bone, tendon, or cartilage bymethods known to the skilled artisan and may be purified by methodsknown in the art. Alternately, the collagen may be purchasedcommercially. Moreover, atelopeptidic or telopeptidic collagen may beused.

[0044] In methods for disc treatment, the tissue growth factor may beapplied to the device as described above or may be introduced into thedisc space or cavity separately (e.g. by injection), or by recombinantDNA methods. For example, a nucleic acid sequence, such as adeoxyribonucleic acid sequence, encoding the particular growth factor,or an active fragment thereof, may be introduced into an appropriatevector. The vector may be a wide variety of vectors typically used ingene transfer protocols, including, for example, retroviral vectors oradenovirus vectors. The vector construct may be synthesized by methodsknown to the skilled artisan. The nucleic acid sequence may be under thecontrol of, and operably linked to, a promoter or other regulatorysequence known in the art. The promoter is preferably one which may beactivated in the target cell by regulatory elements present in thetarget cell.

[0045] In one form of the invention, the disc repair deviceadvantageously includes a therapeutically effective amount of the tissuegrowth factor. What constitutes an effective amount will vary dependingon factors known to the skilled artisan, such as the specific growthfactor used and the extent and type of the damage to the intervertebraldisc. However, the disc repair device will typically contain about 2 mgto about 20 mg of the growth factor. When BMP-9 is used, for example,amounts applied may include about 8 mg to about 12 mg.

[0046] In another aspect of the invention, an intervertebral disctreatment apparatus is provided that includes a disc repair device asdescribed above in combination with a delivery apparatus. Referring nowto FIG. 11, apparatus 61 is shown that includes the generally conicaldisc repair device 21 of FIG. 3, in compressed configuration within theapparatus. The disc treatment apparatus 61 includes tubular or barrelmember 62 having proximal end, a distal end, and a lumen 63 extendinglongitudinally therethrough. Member 62 may be similar to the barrel of asyringe as known in the art. Lumen 63 is configured for housing the discrepair device. Member 62 may be constructed of a wide variety ofmaterials, including polytetrafluoroethylene (Teflon), polyethylene,polyurethane, nylon, glass, or combinations thereof.

[0047] Disc repair delivery apparatus 61 further includes a translationmember 64 at the proximal end of tubular member 62 or forcing the discrepair device 21 distally through lumen 63, through an opening in theannulus fibrosus of a damaged disc, and into the disc cavity of thedisc. Translation member 64 may be an elongated member sized to at leastpartially fit within lumen 63 of member 62 and which is capable ofpushing the disc repair device distally along lumen 63. For example,member 64 may be a plunger including a handle 67, an elongate rod 66,and an internal member 65 substantially spanning the lumen 63 of tubularmember 62, as seen in FIG. 8. Alternately, translation member 64 may bereplaced by other means for translating device 21 along lumen 63. Forexample fluid (e.g. liquid) driven mechanisms may be used. The discrepair device, such as disc repair device 21, is preferably placed in acollapsed or compressed conformation as shown in FIG. 11, advantageouslyby manual force, prior to or upon positioning the device 21 in lumen 63shown in FIG. 12 is a similar disc treatment apparatus 71 exceptincluding therein device 31 of FIG. 4 in compressed configuration,instead of device 21 of FIG. 3.

[0048] In another aspect of the invention, methods of treating anintervertebral disc are provided. In one embodiment, a method oftreating an intervertebral disc includes providing a disc treatmentdevice as described above, such as a fibrous body sized for introductioninto an opening of an annulus fibrosus of a damaged intervertebral disc,and inserting the fibrous body into and through the opening, andblocking effluence from the opening.

[0049] In order to place the disc repair device in the disc cavity, adisc repair delivery apparatus 61 or 71 as described above may be used.As seen in FIGS. 13 and 14, lumen 63 of tubular member 62 is alignedwith the opening in the annulus fibrosus of an intervertebral disc sothat the disc repair device may be pushed distally along lumen 63,through the opening in the annulus and into the disc cavity. The discrepair device will then adopt an expanded conformation as seen in FIG.14.

[0050] Referring now to FIG. 15, shown is an alternative disc treatmentdevice 70, having a generally bulbous end 71 and a generally cylindricalend 72. Bulbous end 71 has a greatest cross-sectional diameter greaterthan that of cylindrical end 72. In one mode of use, device 70 can becompressed and loaded into a cylindrical delivery apparatus, anddelivered through a hole in the annulus and into the disc cavity,preferably first introducing bulbous end 71. Device 70 can then expandwithin the disc cavity.

[0051] With reference now to FIGS. 16-18, illustrated is one mode ofintroducing an elongate implant body through an opening 75 in an annulus76 (e.g. in the location of a rupture opening), and into the disc cavity77. An elongate, cylindrical implant 78 is provided (e.g. a Dacron meshcylinder) having an internal suture 79 or other similar structurerunning therethrough and tied off or otherwise connected at an end 80 ofimplant 78. The other end of suture 79 is tied to a curved needle 81. Todeliver the implant 78, implant 78 can be loaded within a rigid tube 82,with needle 81 and an exposed length of suture 79 extending therefrom.Needle 81 can be passed through opening 75 in annulus 76 and into thedisc cavity 77, and then back through the annulus 76 at a spacedlocation from opening 75, for example at an opposite, posterolateralposition which can be surgically accessed separately. Suture 79 can thenbe pulled to in turn pull implant 78 into the disc cavity 77. Suture 79can then be closely cut or broken so as to partially retract into theannulus.

[0052]FIG. 19 illustrates another apparatus and method for delivering animplant 85, such as a cylindrical Dacron mesh implant, into a disccavity. Implant 85 is loaded within a rigid cannula tube 86, which inturn is passed through the opening in the annulus. In this regard,implant 85 can be loaded in a dry or wet state, preferably a dry,compressed state. Implant 85 is then advanced through the tube 86 usingpush or plunger rod 87, and into the disc cavity. After implantation, adry implant 85 will hydrate, and preferably swell, in situ in the disccavity. If desired, the internal surface of the tube 86 and the exteriorsurface of the rod 87 can be provided with respective cooperatingmembers, such as threads, to assist in controllably advancing implant 85through the tube 86. For example, the inner surface of tube 86 may bearthreads, while the external surface of rod 87 bears correspondingthreads. In this fashion, rotation of rod 87 in relation to tube 86 willadvance rod 87 through tube 86, thereby pushing implant 85 through tube86. In addition, or in the alternative, the implant 85 and/or theinternal surface of tube 86 may be coated with a suitable, biocompatiblelubricant to reduce the friction between the implant 85 and the tube 86during the advancement operation.

[0053] Referring now to FIGS. 20 and 21, shown is another apparatus andmethod for delivering an implant through an annulus opening and into thedisc cavity. A rigid cannula tube 90 defines an opening such as a slot91 in a sidewall thereof. A plurality of openings (e.g. opposed slots)may also be provided. A friction member 92 is mounted over tube 90 andincludes an engaging portion 93 extending into slot 91 so as to providefrictional contact with an implant 94 inside tube 90. In this fashion,implant 94 can be advanced through tube 90 by corresponding advancementof the friction member 92 while its engaging portion 93 frictionallyengages implant 94 through slot 91. In this regard, the frictionalengagement of the implant 94 can optionally be facilitated by thepresence of teeth 95 (e.g. directional as shown) or other roughenedsurface features such as grooves or proturbances on the engaging portion93 of friction member 92, and/or by selection of materials exhibiting acoefficient of friction with the implant suitably high to effectivelyadvance the implant through the tube 90. Further, the frictionalengagement of engaging portion 93 with implant 94 may be releasable, forexample by constructing a deflectable friction member 92 which in arelaxed state disengages engaging portion 93 from the implant, but in acompressed state (e.g. by manually squeezing) engages engaging portion93 with the implant 94, or vice versa.

[0054] A tissue growth factor may be provided on the body of or withinthe device, separately within the disc space of the intervertebral disc,or both. When included separately in the disc space, the tissue growthfactor may be provided within the disc space either before or after thedisc repair device is positioned. Injection of an aqueous fluidcontaining the tissue growth factor into the disc repair device may alsofacilitate expansion of a hydratable, swellable disc repair deviceimmediately after implantation. The disc repair device may be adaptedand dimensional such that when in its expanded or swollen conformation,the device is of a sufficiently large dimension to contact the overlyingand underlying endplates, preferably under compression, so as to securethe device in place in the disc cavity and desirably dissipatecompressive loads from the spine.

[0055] All or a portion of the nucleus pulposus of a damagedintervertebral disc may be removed prior to inserting the device.Moreover, the method may also be followed for preventing escape of thenucleus pulposus from a damaged intervertebral disc, as the disc repairdevices of the present invention may act as a plug.

[0056] It will be understood that various ways of orienting a discrepair device of the present invention in disc cavity are contemplatedin the invention. A single disc repair device can have its longitudinalaxis positioned perpendicular to longitudinal axis of the vertebralcolumn, or two or more devices can be positioned in this manner (e.g.two devices used in a bilateral configuration).

[0057] Disc treatment devices may be inserted through pre-existing (e.g.rupture) opening in the annulus fibrosus or they may be inserted througha cut or incised opening. In one preferred manner of carrying out theinvention, the one or more devices provided to the disc cavity willsubstantially fill the existing void in the cavity, and may also have asufficient vertical dimension to contact the upper and lower surfaceswithin the cavity, for instance so as to be effective to absorbcompressive loads of the spine.

[0058] Delivery apparatuses in accordance with the invention may also beadapted for non- or minimally-invasive delivery of the intervertebraldisc treatment device. For example, such an apparatus can include acannulated device of sufficient length to extend to the disc cavity froman exterior operating position, and the disc treatment device can beadvanced (e.g. in compressed or collapsed form) through and out thedistal end of the cannula and into the disc cavity. For example, such aprocedure may immediately follow a known discectomy protocol, includingfor instance microdiscectomies, endoscopic discectomies, andlaparoscopic discectomies. Further, the delivery of the disc treatmentdevice may be conducted under endoscopic or other similar visualizationtechniques.

[0059] While the invention has been illustrated and described in detailin the drawings and foregoing description, the same is to be consideredas illustrative and not restrictive in character, it being understoodthat only the preferred embodiment has been shown and described and thatall changes and modifications that come within the spirit of theinvention are desired to be protected. In addition, all references citedherein are indicative of the level of skill in the art and are herebyincorporated by reference in their entirety.

What is claimed is:
 1. An intervertebral disc treatment device fortreating an intervertebral disc of a vertebrate while retaining anintact annulus fibrosis, comprising: a compressible fibrous bodyconfigurable to a compressed state for passage through an opening in theannulus fibrosis and into a disc cavity defined by the annulus fibrosis;said body configurable to an expanded state to reside within the disccavity and have a dimension greater than said opening so as to resistexpulsion from said opening; and said body incorporating an effectiveamount of a tissue growth factor.
 2. The device of claim 1, wherein saidfibrous body comprises synthetic fibers.
 3. The device of claim 2,wherein said synthetic fibers comprise a material selected from thegroup consisting of polyamides, polyesters, polyethylenes,polyacrylonitriles, polyurethanes, polypropylenes and mixtures thereof.4. The device of claim 2, wherein said synthetic fibers comprisepolyester.
 5. The device of claim 1, wherein said fibrous body iscomprised of fibers coated with a solid carrier matrix comprising thetissue growth factor.
 6. The device of claim 1, wherein said fibrousbody is comprised of natural fibers.
 7. The device of claim 6, whereinsaid natural fibers are collagen.
 8. The device of claim 6, wherein saidnatural fibers are elastin.
 9. The device of claim 1, wherein said bodyincorporates a tissue growth composition comprising a tissue growthfactor within a biocompatible carrier.
 10. The device of claim 9,wherein said tissue growth composition is incorporated within said body.11. The device of claim 9, wherein said tissue growth composition isbound to an exterior surface of said body.
 12. The device of claim 11,wherein said biocompatible carrier comprises a polymer.
 13. The deviceof claim 12, wherein said polymer is a naturally occurring polymer. 14.The device of claim 12, wherein said polymer is collagen.
 15. The deviceof claim 9, wherein said tissue growth factor is selected from the groupconsisting of Transforming Growth Factor-beta (TGF-B) and members of theTGF-B superfamily, Fibroblast Growth Factor (FGF) and members of the FGFfamily, Platelet Derived Growth Factor (PDGF) and members of the PDGFfamily, members of the hedgehog family of proteins, interleukins (Ils),Insulin-like Growth Factor (IGF) and members of the IGF family,colony-stimulating factor (CSF) and members of the CSF family, GrowthDifferentiation Factors (GDFs), Cartilage Derived Growth Factors(CDGFs), Cartilage Derived Morphogenic Proteins (CDMPs), BoneMorphogenetic Proteins (BMPs), and mixtures thereof.
 16. The device ofclaim 9, wherein said tissue growth factor is a Bone MorphogeneticProtein.
 17. The device of claim 15 or 16, wherein said tissue growthfactor is a recombinant human protein.
 18. The device of claim 16,wherein said bone morphogenetic protein is selected from the groupconsisting of BMP-1, BMP-2, BMP-3, BMP-4, BMP-5, BMP-6, BMP-7, BMP-8,BMP-9, BMP-10, BMP-11, BMP-12, BMP-13, BMP-14, BMP-15, BMP-16, BMP-17,BMP-18, and mixtures or heterodimers thereof.
 19. The device of claim 1,wherein said fibrous body is a multi-layered body.
 20. The device ofclaim 1, wherein said body is cylindrical.
 21. An intervertebral discrepair device, comprising a mesh sized for introduction into a disccavity, said mesh incorporating an effective amount of a tissue growthfactor to promote tissue growth within the disc cavity.
 22. The deviceof claim 21, wherein said mesh is comprised of synthetic fibers.
 23. Thedevice of claim 22, wherein said synthetic fibers comprise a materialselected from the group consisting of polyamides, polyesters,polyacrylonitrile, polyurethanes, polypropylene and mixtures thereof.24. The device of claim 22, wherein said synthetic fibers comprisepolyester.
 25. The device of claim 21, wherein said mesh is comprised ofnatural fibers.
 26. The device of claim 25, wherein said natural fibersare selected from the group consisting of elastin and collagen.
 27. Thedevice of claim 21, which incorporates a tissue growth compositionincluding the tissue growth factor and a biocompatible carrier.
 28. Thedevice of claim 27, wherein said tissue growth factor is selected fromthe group consisting of Transforming Growth Factor-beta (TGF-B) andmembers of the TGF-B superfamily, Fibroblast Growth Factor (FGF) andmembers of the FGF family, Platelet Derived Growth Factor (PDGF) andmembers of the PDGF family, members of the hedgehog family of proteins,interleukins (Ils), Insulin-like Growth Factor (IGF) and members of theIGF family, colony-stimulating factor (CSF) and members of the CSFfamily, Growth Differentiation Factors (GDFs), Cartilage Derived GrowthFactors (CDGFs), Cartilage Derived Morphogenic Proteins (CDMPs), BoneMorphogenetic Proteins (BMPs), and mixtures thereof.
 29. The device ofclaim 27, wherein said tissue growth factor is a bone morphogeneticprotein.
 30. The device of claim 27, wherein said biocompatible carrierincludes a natural or synthetic polymer.
 31. An intervertebral discrepair device, comprising a bioresorbable body sized for introductioninto a disc cavity, said body incorporating an effective amount of atissue growth factor.
 32. The device of claim 31, wherein saidbioresorbable body is comprised of natural fibers.
 33. The device ofclaim 32, wherein said natural fibers are selected from the groupconsisting of elastin and collagen.
 34. The device of claim 31, whichincorporates a tissue growth composition including a tissue growthfactor and a biocompatible carrier.
 35. The device of claim 34, whereinsaid tissue growth factor is selected from the group consisting ofTransforming Growth Factor-beta (TGF-B) and members of the TGF-Bsuperfamily, Fibroblast Growth Factor (FGF) and members of the FGFfamily, Platelet Derived Growth Factor (PDGF) and members of the PDGFfamily, members of the hedgehog family of proteins, interleukins (Ils),Insulin-like Growth Factor (IGF) and members of the IGF family,colony-stimulating factor (CSF) and members of the CSF family, GrowthDifferentiation Factors (GDFs), Cartilage Derived Growth Factors(CDGFs), Cartilage Derived Morphogenic Proteins (CDMPs), BoneMorphogenetic Proteins (BMPs), and mixtures thereof.
 36. The device ofclaim 34, wherein said tissue growth factor is a bone morphogeneticprotein.
 37. The device of claim 34, wherein said biocompatible carrierincludes a natural or synthetic polymer.
 38. An apparatus for treatingan intervertebral disc, comprising: (a) a disc treatment devicecomprising a fibrous body sized for introduction into a disc cavity of adamaged disc, said body incorporating an effective amount of a tissuegrowth factor; and (b) a delivery apparatus adapted to retain andselectively release the disc treatment device into the disc cavity. 39.The apparatus of claim 38, wherein said delivery apparatus comprises: amember having a proximal end, a distal end and a lumen extendinglongitudinally therethrough, said disc treatment device disposed in saidlumen; and means at the proximal end of said member for forcing saiddisc treatment device distally through said lumen and into said disccavity of said damaged disc.
 40. A method for treating an intervertebraldisc, comprising: (a) providing a fibrous body sized for introductioninto a disc cavity of a damaged disc; (b) introducing said fibrous bodyinto the disc cavity of said intervertebral disc through an opening insaid disc; and (c) providing a tissue growth factor within the disccavity of said intervertebral disc.
 41. The method of claim 40, whereinsaid body is in a compressed configuration prior to said introducing,and expands within the disc cavity after said introducing.
 42. Themethod of claim 40, including sealing said opening after saidintroducing.
 43. The method of claim 40, comprising removing a portionof the nucleus pulposus of said disc prior to said introducing.
 44. Themethod of claim 40, wherein said tissue growth factor is combined with abiocompatible carrier.
 45. The method of claim 44, wherein said tissuegrowth factor stimulates the formation of nucleus pulposus, annulus,ligament, tendon and/or fibroblast cells.
 46. The method of claim 40,wherein said tissue growth factor is non-osteogenic.
 47. The method ofclaim 40, wherein said fibrous body is bioresorbable.
 48. A method oftreating an intervertebral disc, comprising introducing a fibrous bodyinto a disc cavity of a damaged disc between adjacent vertebrae, saidbody incorporating an effective amount of a tissue growth composition tostimulate soft tissue formation within the disc cavity sufficient toaccommodate at least a portion of compressive loads occurring betweenthe adjacent vertebrae.
 49. The method of claim 48, wherein said fibrousbody is comprised of synthetic fibers.
 50. A method of treating anintervertebral disc, comprising: (a) providing a fibrous body sized forintroduction into an opening of an annulus fibrosus of said disc; (b)inserting said fibrous body through said opening, said body therebyblocking effluence from said opening; and (c) providing a tissue growthcomposition within the disc space of said intervertebral disc.
 51. Themethod of claim 50, wherein said fibrous body is comprised of syntheticfibers.
 52. A method of preventing effluence from a disc cavity of adamaged intervertebral disc having an annulus Fibrosus having anopening, said method comprising inserting a fibrous plug into the cavityof said disc so as to block effluence from said opening.
 53. The methodof claim 52, wherein said plug comprises an effective amount of a tissuegrowth composition to stimulate disc repair.
 54. A method for treating adamaged intervertebral disc, comprising: (a) providing an opening in anannulus fibrosis of the damaged intervertebral disc; (b) passing anon-prosthetic delivery body through said opening and into a disc cavitydefined by the annulus fibrosis, the delivery body incorporating atissue growth factor; and (c) the delivery body releasing the tissuegrowth factor in the disc cavity and promoting tissue growth in the disccavity.
 55. A method for treating a damaged intervertebral disc in avertebrate, the intervertebral disc having an annulus fibrosis having arupture opening, the method comprising introducing a tissue growthfactor into a disc cavity of the ruptured intervertebral disc, andsealing the rupture opening of the annulus with a sealant device.
 56. Amethod of treating an intervertebral disc, comprising: introducing aload-bearing, polyester implant into an opening of an annulus fibrosusof said disc.